Skip to main content
Back

Transcription in Eukaryotes quiz #1

Control buttons has been changed to "navigation" mode.
1/10
  • What are the functions of RNA polymerase in eukaryotic transcription?
    RNA polymerases synthesize RNA from a DNA template. In eukaryotes, RNA polymerase I transcribes ribosomal RNA, RNA polymerase II transcribes messenger RNA, and RNA polymerase III transcribes tRNA and some other small RNAs.
  • Which RNA polymerase is responsible for transcribing mRNA from eukaryotic structural genes?
    RNA polymerase II is responsible for transcribing mRNA from eukaryotic structural genes.
  • If the base sequence of the template DNA strand reads GCCATTAC, what is the base sequence of the mRNA produced?
    The mRNA sequence will be CGGUAAUG, with uracil (U) replacing thymine (T).
  • What is the role of general transcription factors in eukaryotic transcription initiation?
    General transcription factors bind to the promoter region and help recruit RNA polymerase II to form the pre-initiation complex necessary for transcription to begin.
  • What is the TATA box and where is it typically located relative to the transcription start site?
    The TATA box is a DNA sequence found about 30 base pairs upstream of the transcription start site and serves as a binding site for general transcription factors.
  • How does phosphorylation of the RNA polymerase II C-terminal domain (CTD) affect transcription?
    Phosphorylation of the CTD activates RNA polymerase II, allowing it to transition from initiation to elongation and begin synthesizing RNA.
  • Why does eukaryotic RNA polymerase II often transcribe beyond the end of a gene's coding sequence?
    Eukaryotic transcription lacks a defined termination sequence, so RNA polymerase II may continue transcribing hundreds or thousands of nucleotides past the coding region before disengaging.
  • What is the difference between cis-acting and trans-acting regulatory elements in transcription?
    Cis-acting elements are located on the same chromosome as the gene they regulate, while trans-acting elements can be located on different chromosomes.
  • What is the function of enhancers and silencers in eukaryotic transcription?
    Enhancers increase the rate of transcription, while silencers repress or decrease transcription of specific genes.
  • How can regulatory elements located far from a gene still influence its transcription?
    The three-dimensional organization of chromatin in the nucleus allows distant regulatory elements to physically interact with promoters and affect gene expression.